It's less likely if you wait in the Group menu until at least one person has joined. It happens almost all the time if you invite someone and then immediately close the Group menu to get on with the game.
Anyone knows if the group leader bug will ever be fixed, or if it will never, because it's not a bug but an awesome feature of the game to keep us entertained ?
BTW, is there any other bug that's been going on since the beta and that has still not been addressed apart this one ?